U.S. Secret Service Director Julia Pierson came under sharp criticism from members of Congress, who pressed her to explain how an intruder was able to evade security and enter the main floor of the White House 10 days ago.

Republican and Democratic lawmakers expressed concern about the safety of President Barack Obama and his family while they are at home.

Democrats and Republicans on the House Oversight and Government Reform Committee often argue bitterly with each other. On Tuesday, though, they turned their anger and frustration on Secret Service Director Pierson.

Bi-partisan outrage

Republican Representative Jason Chaffetz was outraged that Pierson praised what she said was the “tremendous restraint” Secret Service agents showed after the incident on September 19 when a man with a knife was able to run all the way into the East Room of the presidential mansion before he was apprehended.

“Tremendous restraint is not the goal and the objective. It sends a very mixed message. The message should be overwhelming force,” said Chaffetz.

Pierson promised a comprehensive investigation into the failures that allowed the intruder to jump a fence, cross the grounds and enter the White House, and said she would take action if needed.

“It is clear that our security plan was not properly executed. This is unacceptable, and I take full responsibility, and I will make sure that it does not happen again,” she stated.

Questions of leadership

Her response was not good enough for many of the lawmakers on the panel, including Democrat Stephen Lynch. “And I wish to God you protected the White House like you are protecting your reputation here today," he said. "I wish you spent that time and that effort to protect the American president.”

Lynch said he has serious questions about Pierson's leadership and that he fears for the safety of the president and the first family within the confines of the White House.

Washington, D.C. Delegate Eleanor Holmes Norton pointed out that as the first African-American U.S. president, Obama faces even more danger.

“According to threat assessments, this president has had three times as many threats as his predecessors,” said Norton.

Mixed signals alleged

Pierson was also asked about another incident in 2011 when a man fired into the White House and it took several days for the Secret Service to realize that the building had been hit.

Several lawmakers blamed Pierson for sending mixed signals about whether agents could use lethal force if they felt the president is in danger.

Some said the height of the White House fence is not the problem, but that several layers of security failed to stop the fence-jumper until he had crossed the lawn, opened the door, and run through the main floor of the White House.

The president and his daughters had left the building just minutes before the intruder came in.